Automatic safety device for cloth cutting machines



June 20, 1933. J. A, COHEN 1,915,049

AUTOMATIC SAFETY DEVICE FOR CLOTH CUTTING MACHINES Filed April 30, 1951 IN VEN T OR & ATTORNEY Patented June 20, 1933 FATENT QFFEQE JACOB A. COHEN, OF NEW YORK, N. Y.

AUTOMATIC SAFETY DEVICE FOR CLOTH CUTTING MACHINES Application filed April 30,

This invention relates to new and useful improvements in an automatic safety device for cloth cutting machines.

I The invention has for an object the con struction of an automatic safety device for cloth cutting machine which is characterized by a guard frame adj ustably mounted so as to cover up the disc cutting knife of the cutting device, and a means for rendering the cutting l device inoperative when the guard is moved out of position.

It is a still further object of this invention to provide an adjustable bar upon the body of the cutting device for adjustably supporting the guard frame.

As another object, this invention proposes forming the guard from opposite framed sections capable of being disposed on opposite sides of the disc knife. I

Furthermore, it is also proposed to pivotally support the guard frames so that either one may be manually moved out of place from protecting the knife whenever this becomes desirable.

As a still further object of this invention, it is proposed to provide switches upon the guard frame operable to cut the circuit of the motor of the cutting device when either one or both of the guard frame sections are moved.

.45 tion, and of the objects and advantages there of, reference will be had to the following description and accompanying drawing, and to the appended claims in which the various novel features of the invention are more par- 59 ticularly set forth.

1931. Serial No. 533,978.

In the accompanying drawing, forming a material part of this disclosure 2- Fig. l is a side elcvational view of an automatic safety device attached upon a cutting machine.

Fig. 2 is a horizontal sectional view taken 011 the line 22 of Fig. 1.

Fig. 3 is an elevational view looking in the direction of the line 3-3 of Fig. 2.

Fig. 4 is a side elevational view of Fig. 2.

Fig. 5 is a fragmentary elevational view looking in the direction of the line 5 5 of Fig. 2.

Fig. 6 is a schematic wiring diagram of the electric portion of the device.

Fig. 7 is a perspective view of a guard, showing a modified form of construction.

The automatic safety device for cloth cut ting machines, according to this invention, comprises a pair of guard frames 10 adjustably supported on opposite sides of the disc knife ll of the cloth cutting machine 12. The machine 12 may be of any design and construction. As shown in the drawing, it is provided with a lamp 13 for illumination and a handle 14; for manipulation. A grinding stone 15 is also shown upon the machine movable so as to act against the cutting edge of the disc blade. The details and the operation of the cutting machine will not be gone into since they form no part of this invention and are generally known.

A vertical bar 16 is adjustably supported upon the body of the cutting machine by reason of a setscrew 17 engaging through a slot 18 thereon. The top end 19 of this bar is turned around so as to form a loop for receiving ones finger to allow raising or lowering. The pair of guard frames 10 are fixed upon a bracket 20 attached upon the lower end of the bar 16. This bracket is of substantially U-shape and is provided with an end set screw 21 for engaging against one of the ends of the bar and opposite side set screws 22 for engaging against the side of the bar to accomplish clamping in place.

A bracket 20 has its outer arm sections 20 separate and hingedly connected at the points 23 by switch stems 33. Springs 2st are attached upon one of the stationary arm 10!) sections and engage over the pivoted arm sections so as to move them into aligned positions. Stop pieces 25 are attached upon the stationary arm sections and act against the sides of movable arm sections to limit possible motion to aligned positions only.

Each of the guard frames 10 comprises a wire frame 26 covered by wire gauze 27. The wire frames 26 are bent so as to be narrow at 28 and then flare outwards at their lower extremities 29 to rest against the cutting table. One of the corners 30 on one of the guard frames is bent outwards so as to allow the grinding stone 15 to move inwards against the cutting edge of the disc knife 11.

A stationary cam 31 is attached upon the body of the cutting machine and extends downwards to a position so as to be capable of prying the hinged arm sections 20 of the bracket 20 away from each other when the guard is raised due to moving the vertical bar 16 upwards. "he prying away of the arm sections causes cutting of the electric current in the motor of the cutting machine. For this purpose, a switch 32 is mounted upon each of the stationary arm sections of the bracket 20 and have their switch stems 3S fixed in the arm sections 20 as the stems pass through the points 23 so that as the outer ends of the arms are moved, the stems 33 are revolved around their central axis to operate the switches. These switches are so constructed that when the arms are parallel, as shown in Fig. 2, the circuit is closed and when either or both of the arm sections are moved, as for example as indicated by the dot and dash lines the switches are in their opened positions. Each of the switches 32 are connected in series with the electric motor 36 which is the motor of the cutting machine device 12. This is schematically Shown in Fig. (3. The construction of the switches 32 is conventional and generally known and form no part of this invention and for this reason is not illustrated in the drawing.

In Fig. 4, the top 26 of the wire frame 26 is angularly shaped and the wire gauze .27 is formed by wires extending horizontally. It is to be understood that any type of transparent guard may be used in connection with my device.

The operation of the device can be traced by assuming the guard in the position illustrated in Fig. 1. The cutting machine may be used in the conventional manner for cutting cloth and the guard serves to shield the cutting edge of the knife. If for some reason or other, access is desired to the cutting edge, one or both of the guard frames 10 may be pivoted outwards. Pivoting of these frames serves to operate the switches for cutting the circuit through the motor to stop the operation of the cutting device. Then again, the bar 16 may be raised so as to move the guard away from its protecting position relative to the cutting knife. After the bar 16 is moved upwards, the cam 31 prys the pivotal arm sections of the bracket 20 outwards and causes operation of the switch of the cutting of the current from the motor.

While I have shown and described the preferred embodiment of my invention, it is to be understood that I do not limit myself to the precise construction herein disclosed and the right is reserved to all changes and modifications coming within the scope of the invention as defined in the appended claims.

Having thus described my invention, what I claim as new, and desire to secure by United States Letters Patent is 1. An automatic safety device for cloth cutting machines, comprising a pair of guard frames supported on opposite sides of the knife of the machine and vertically adjustable so as to be capable of being raised, means for causing the inoperation of the cutting machine upon rotating of the guard frames out of place, and means for rotating the guard frames out of place upon raising of the guard frames.

2. In an automatic safety device for cloth cutting machines, comprising a pair of guard frames supported on opposite sides of the 7 knife of the machine and vertically adjustable so as to be capable of being raised, means for causing the inoperation of the cutting machine upon motion of the guard frames out of place, and means for rotating the guard frames out of place upon raising of the guard frames, said vertical support of the guard frames being accomplished by a rod slidably mounted upon the device, and means for supporting the guard frames on said rod.

3. In combination with a cloth cutting machine having a motor driven knife, an adjustable rod mounted on said cloth cutting machine, a bracket fixed on the lower end of said rod, a pair of parallel arms pivotally mounted on said bracket, means for holding said arms in parallel condition, guard frames mounted upon said arms for location on opposite sides of said knife, a stationary cam on said cutting device for prying the arms away from each other when the guard is raised, and means for cutting the circuit through the electric motor upon outward plvoting of one or both of said arms.

4. In combination with a cloth cuttin machine having a motor driven knife, an a justable rod mounted on said cloth cutting machine, a bracket fixed on the lower end of said rod, a pair of parallel arms p'ivotally mounted on said bracket, means for holding said arms in parallel condition, guard frames mounted upon said arms for location on opposite side of said knife, a stationary cam on said cutting device forprying the arms away from each other when the guard is raised, and means for cutting the circuit through the electric motor upon outward pivoting of one or both of said arms, comprising switches connected in series with the motor and mounted upon the pivot points of the arms.

5. In combination with a cloth cutting machine having a motor driven knife, and an adjustable rod mounted on said cloth cutting machine, a bracket fixed on the lower end of said rod, a pair of parallel arms pivotally mounted on said bracket, means for holding said arms in parallel condition, guard frames mounted upon said arms for location on opposite sides of said knife, a stationary cam on said cutting device for prying the arms away from each other when the guard is raised, and means for cutting the circuit through the electric motor upon outward pivoting of one or both of said arms, comprising switches fixed upon the bracket, operating stems projecting from said switches and connected with said pivotally mounted arms.

6. In combination with a cloth cutting machine having a motor driven knife, and an adjustable rod mounted on said cloth cutting machine, a bracket fixed on the lower end of said rod, a pair of parallel arms pivotally mounted on said bracket, means for holding said arms in parallel condition, guard frames mounted upon said arms for location on opposite sides of said knife, a stationary cam on said cutting device for prying the arms away from each other when the guard is raised, and means for cutting the circuit through the electric motor upon outward pivoting of one or both of said arms, comprising switches fixed upon the bracket, operating stems projecting from said switches and connected with said pivotally mounted arms, said operating stems pivotally connecting said arms with said bracket.

In testimony whereof I have aflixed my signature.

JACOB A. COHEN. 

